Aerosol generating assembly

ABSTRACT

An assembly for generating an inhalable medium, a cartridge for use in an assembly for generating an inhalable medium, a method of generating an inhalable medium, a kit, a liquid pod, and a nicotine-containing pod.

PRIORITY CLAIM

The present application is a National Phase entry of PCT Application No.PCT/GB2021/050634, filed Mar. 12, 2021, which claims priority from GBApplication No. 2003675.2, filed Mar. 13, 2020, each of which is herebyfully incorporated herein by reference.

TECHNICAL FIELD

The present invention relates, without limitation, to an assembly forgenerating an inhalable medium, a cartridge for use in an assembly forgenerating an inhalable medium, a method of generating an inhalablemedium, a kit, a liquid pod, and a nicotine-containing pod.

BACKGROUND

Smoking articles such as cigarettes, cigars and the like burn tobaccoduring use to create tobacco smoke. Alternatives to these types ofarticles, release compounds without burning to form an inhalable medium.

Examples of such products are heating devices, includinge-cigarette/heat-not-burn hybrid devices, also known as electronictobacco hybrid devices. These hybrid devices contain a liquid that isvaporized by heating to produce an inhalable vapor and/or aerosol. Theliquid may contain flavorings and/or aerosol-generating substances, suchas glycerol and in some instances, nicotine. The vapor and/or aerosolpasses through a substrate in the device and entrains one or moreconstituents of the substrate to produce the inhaled medium. Thesubstrate material may be, for example, tobacco, other non-tobaccoproducts or a combination, such as a blended mix, that may or may notcontain nicotine.

SUMMARY

According to a first aspect of the present invention, there is providedan aerosol generating assembly comprising:

a solid, nicotine-containing material having a pH of at least 7;

an aerosolizable liquid comprising an acid, and having a pH of at least2 and less than 7; and

wherein the assembly is configured to heat the aerosolizable liquid toform a vapor and/or an aerosol, wherein the vapor/aerosol is contactedwith the solid, nicotine-containing material to entrain one or morecomponents thereof, and thus forming an inhalable medium.

The assembly may be referred to as an electronic tobacco hybrid device.In some cases, the solid, nicotine-containing material comprises atobacco material. In some cases, the solid, nicotine-containing materialis tobacco material. In some cases, the assembly is configured such thatthe solid, nicotine-containing material is heated only by thevapor/aerosol.

In some cases, the pH of the solid, nicotine-containing material is offrom 8 to 9.5 of from 8.5 to 9. In some cases, the aerosolizable liquidhas a pH of from 4 to 5 or from 4.3 to 4.8. In some cases, thedifference between the pH of the solid nicotine-containing material andthe pH of the aerosolizable liquid is of from 3.0 and 5.5. In somecases, the acid has a vapor pressure at 25° C. of from 0.1 Pa to 2.5kPa. In some cases, the aerosolizable liquid has an amount of acid offrom 0.001 to 5% by weight. In some cases, the acid has a pKa greaterthan 0.5, greater than 1, greater than 1.5, greater than 2, greater than2.5 or greater than 3, suitably, of from 3.7 to 4.3.

According to a second aspect of the present invention, there is providedan aerosol generating assembly comprising:

a solid, nicotine-containing material having a pH of at least 7;

an aerosolizable liquid comprising an acid, the acid with a pKa greaterthan 0.5; and

wherein the assembly is configured to heat the aerosolizable liquid toform a vapor and/or an aerosol, wherein the vapor/aerosol is contactedwith the solid, nicotine-containing material to entrain one or morecomponents thereof, and thus forming an inhalable medium.

The assembly may be referred to as an electronic tobacco hybrid device.In some cases, the solid, nicotine-containing material comprises atobacco material. In some cases, the solid, nicotine-containing materialis tobacco material. In some cases, the assembly is configured such thatthe solid, nicotine-containing material is heated only by thevapor/aerosol.

In some cases, the pKa of the acid is greater than 3 or from 3.7 to 4.3.In some cases, the pH of the solid, nicotine-containing material is offrom 8 to 9.5 or from 8.5 to 9. In some cases, the aerosolizable liquidhas a pH of at least 2 and less than 7, or from 4 to 5, suitably from4.3 to 4.8. In some cases, the difference between the pH of the solidnicotine-containing material and the pH of the aerosolizable liquid isof from 3.0 and 5.5. In some cases, the acid has a vapour pressure at25° C. of from 0.1 Pa to 2.5 kPa. In some cases, the aerosolizableliquid has an amount of acid of from 0.001 to 5% by weight.

According to a further aspect of the present invention, there isprovided a cartridge for use in an assembly for generating an inhalablemedium, the cartridge comprising an aerosolizable liquid comprising anacid in a first chamber, the aerosolizable liquid having a pH of atleast 2 and less than 7, and a solid, nicotine-containing materialhaving a pH of at least 7 in a second chamber. In some cases, theaerosolizable liquid has a pH of from 4 to 5 or from 4.3 to 4.8. In somecases, the difference between the pH of the solid nicotine-containingmaterial and the pH of the aerosolizable liquid is of from 3.0 and 5.5.In some cases, the acid has a pKa greater than 0.5 or greater than 3,suitably, of from 3.7 to 4.3. In some cases, the solid,nicotine-containing material has a pH of from 8 to 9.5 or from 8.5 to 9.In some cases, the acid has a vapour pressure at 25° C. of from 0.1 Pato 2.5 kPa. In some cases, the aerosolizable liquid has an amount ofacid of from 0.001 to 5% by weight.

The cartridge may be for use in an assembly that may be referred to asan electronic tobacco hybrid device. In some cases, the solid,nicotine-containing material comprises a tobacco material. In somecases, the solid, nicotine-containing material is tobacco material. Insome cases, the cartridge is for use in an assembly that is configuredsuch that the solid, nicotine-containing material is heated only by thevapor/aerosol.

According to a further aspect of the present invention, there isprovided a cartridge for use in an assembly for generating an inhalablemedium, the cartridge comprising an aerosolizable liquid comprising anacid in a first chamber, the acid having a pKa greater than 0.5, and asolid, nicotine-containing material having a pH of at least 7 in asecond chamber. In some cases, the acid has a pKa of greater than 3 orfrom 3.7 to 4.3. In some cases, the aerosolizable liquid has a pH ofless than 7, or of from 4 to 5, suitably from 4.3 to 4.8. In some cases,the solid, nicotine-containing material has a pH of from 8 to 9.5 orfrom 8.5 to 9. In some cases, the difference between the pH of the solidnicotine-containing material and the pH of the aerosolizable liquid isof from 3.0 and 5.5. In some cases, the acid has a vapour pressure at25° C. of from 0.1 Pa to 2.5 kPa. In some cases, the aerosolizableliquid has an amount of acid of from 0.001 to 5% by weight.

The cartridge may be for use in an assembly that may be referred to asan electronic tobacco hybrid device. In some cases, the solid,nicotine-containing material comprises a tobacco material. In somecases, the solid, nicotine-containing material is tobacco material. Insome cases, the cartridge is for use in an assembly that is configuredsuch that the solid, nicotine-containing material is heated only by thevapor/aerosol.

According to a further aspect of the present invention, there isprovided a method of generating an inhalable medium using an assemblycomprising an aerosolizable liquid comprising an acid, the aerosolizableliquid having a pH of at least 2 and less than 7, and a solid,nicotine-containing material having a pH of at least 7, the methodcomprising:

-   -   heating the aerosolizable liquid to form a vapor and/or an        aerosol;    -   forming an inhalable medium, by contacting the aerosolizable        liquid in the form of a vapor and/or an aerosol with the solid,        nicotine-containing material to entrain one or more components        thereof. In some cases, the aerosolizable liquid has a pH of        from 4 to 5 or from 4.3 to 4.8. In some cases, the acid has a        pKa greater than 0.5 or greater than 3, suitably, of from 3.7 to        4.3. In some cases, the solid, nicotine-containing material has        a pH of from 8 to 9.5 or from 8.5 to 9. In some cases, the        difference between the pH of the solid nicotine-containing        material and the pH of the aerosolizable liquid is of from 3.0        and 5.5. In some cases, the acid has a vapor pressure at 25° C.        of from 0.1 Pa to 2.5 kPa. In some cases, the aerosolizable        liquid has an amount of acid of from 0.001 to 5% by weight.

In some cases, the solid, nicotine-containing material comprises atobacco material. In some cases, the solid, nicotine-containing materialis a tobacco material. In some cases, the assembly is configured suchthat the solid, nicotine-containing material is heated only by thevapor/aerosol.

According to a further aspect of the present invention, there isprovided a method of generating an inhalable medium using an assemblycomprising an aerosolizable liquid comprising an acid, the acid with apKa greater than 0.5, and a solid, nicotine-containing material having apH of at least 7, the method comprising:

-   -   heating the aerosolizable liquid to form a vapor and/or an        aerosol;    -   forming an inhalable medium, by contacting the aerosolizable        liquid in the form of a vapor and/or an aerosol with the solid,        nicotine-containing material to entrain one or more components        thereof. In some cases, the acid has a pKa of greater than 3 or        from 3.7 to 4.3. In some cases, the aerosolizable liquid has a        pH of at least 2 and less than 7, or from 4 to 5, suitably from        4.3 to 4.8. In some cases, the solid, nicotine-containing        material has a pH of from 8 to 9.5 or from 8.5 to 9. In some        cases, the difference between the pH of the solid        nicotine-containing material and the pH of the aerosolizable        liquid is of from 3.0 and 5.5. In some cases, the acid has a        vapor pressure at 25° C. of from 0.1 Pa to 2.5 kPa. In some        cases, the aerosolizable liquid has an amount of acid of from        0.001 to 5% by weight.

The assembly may be referred to as an electronic tobacco hybrid device.In some cases, the solid, nicotine-containing material comprises atobacco material. In some cases, the solid, nicotine-containing materialis a tobacco material. In some cases, the assembly is configured suchthat the solid, nicotine-containing material is heated only by thevapor/aerosol.

According to a fifth aspect of the present invention, a use is providedfor an acidic vapor and/or aerosol to extract nicotine from a solid,nicotine-containing material having a pH of at least 7, wherein the rateof nicotine extraction exceeds the rate of nicotine-salt formation inthe solid, thereby providing an increased nicotine content in the vaporand/or aerosol as compared to using a neutral vapor and/or aerosol.

According to a further aspect of the present invention, there isprovided a kit comprising:

(i) a liquid pod containing an aerosolizable liquid comprising an acid,the aerosolizable liquid having a pH of at least 2 and less than 7; and

(ii) a nicotine-containing pod, containing a solid, nicotine-containingmaterial having a pH of at least 7;

wherein the liquid and nicotine-containing pod are configured for use inan assembly for use in generating an inhalable medium, the assemblybeing such that in use, an inhalable medium is generated by contactingthe aerosolizable liquid in the form of a vapor vapour and/or an aerosolwith the solid, nicotine-containing material to entrain one or morecomponents thereof.

The liquid and nicotine-containing pod may be for use in an assemblythat may be referred to as an electronic tobacco hybrid device. In somecases, the solid, nicotine-containing material comprises a tobaccomaterial. In some cases, the solid, nicotine-containing material is atobacco material. In some cases, the liquid and nicotine-containing podare configured for use in an assembly that is configured such that thesolid, nicotine-containing material is heated only by the vapor/aerosol.

In some cases, the aerosolizable liquid has a pH of from 4 to 5 or from4.3 to 4.8. In some cases, the pKa of the acid is greater than 0.5 orgreater than 3, suitably of from 3.7 to 4.3. In some cases, the vaporpressure of the acid at 25° C. is of from 0.1 Pa to 2.5 kPa. In somecases, the pH of the solid, nicotine-containing material is of from 8 to9.5 or from 8.5 to 9. In some cases, the difference between the pH ofthe solid nicotine-containing material and the pH of the aerosolizableliquid is of from 3.0 and 5.5. In some cases, the aerosolizable liquidhas an amount of acid of from 0.001 to 5% by weight.

According to a further aspect of the present invention, there isprovided a kit comprising:

(i) a liquid pod containing an aerosolizable liquid comprising an acid,the acid with a pKa greater than 0.5; and

(ii) a nicotine-containing pod, containing a solid, nicotine-containingmaterial having a pH of at least 7;

wherein the liquid and nicotine-containing pod are configured for use inan assembly for use in generating an inhalable medium, the assemblybeing such that in use, an inhalable medium is generated by contactingthe aerosolizable liquid in the form of a vapor and/or an aerosol withthe solid, nicotine-containing material to entrain one or morecomponents thereof.

The liquid and nicotine-containing pod may be for use in an assemblythat may be referred to as an electronic tobacco hybrid device. In somecases, the solid, nicotine-containing material comprises a tobaccomaterial. In some cases, the solid, nicotine-containing material is atobacco material. In some cases, the liquid and nicotine-containing podare configured for use in an assembly that is configured such that thesolid, nicotine-containing material is heated only by the vapor/aerosol.

In some cases, the pKa of the acid is greater than 3 or from 3.7 to 4.3.In some cases, the pH of the solid, nicotine-containing material is offrom 8 to 9.5 or from 8.5 to 9. In some cases, the aerosolizable liquidhas a pH of at least 2 and less than 7, or from 4 to 5, suitably from4.3 to 4.8. In some cases, the difference between the pH of the solidnicotine-containing material and the pH of the aerosolizable liquid isof from 3.0 and 5.5. In some cases, the acid has a vapor pressure at 25°C. of from 0.1 Pa to 2.5 kPa. In some cases, the aerosolizable liquidhas an amount of acid of from 0.001 to 5% by weight.

To the extent that they are compatible, features described in relationto one aspect of the invention are explicitly disclosed in combinationwith each and every other aspect. For instance, features described inrelation to the assembly, cartridge, nicotine-containing pod, liquid podor kit are explicitly disclosed in combination with the each of theothers of the assembly, cartridge, nicotine-containing pod, liquid podand kit. Specifically, features of the solid, nicotine-containingmaterial and aerosolizable liquid comprising an acid as described hereinare explicitly disclosed in combination with the assembly, cartridge,nicotine-containing pod, liquid pod, and kit embodiments of theinvention. Similarly, features described in relation to apparatus areexplicitly disclosed in combination with method and use aspects of theinvention, and vice versa.

Further features and advantages of the invention will become apparentfrom the following description of preferred embodiments of theinvention, given by way of example only, which is made with reference tothe accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Examples of assemblies and cartridges for generating an inhalable mediumaccording to the invention are described below with reference to theaccompanying drawings, in which:

FIG. 1 shows a schematic longitudinal cross-sectional view of an exampleof an assembly for generating an inhalable medium;

FIG. 2 shows a schematic longitudinal cross-sectional view of anotherexample of an assembly for generating an inhalable medium;

FIG. 3 shows a schematic longitudinal cross-sectional view of anotherexample of an assembly for generating an inhalable medium;

FIG. 4 shows a schematic longitudinal cross-sectional view of an exampleof a cartridge having a liquid chamber and an integral chamber for solidmaterial;

FIG. 5 shows a schematic longitudinal cross-sectional view of an exampleof a cartridge having a liquid chamber and a detachable chamber forsolid material;

FIG. 6 shows nicotine delivery from assemblies according to embodimentsof the invention, and a comparative assembly.

DETAILED DESCRIPTION OF THE DRAWINGS

The present invention relates to improving the taste of an inhalableaerosol, and increasing the amount of nicotine delivery in an assemblyfor use in a hybrid device, where the nicotine has been pH-treated toraise its pH.

At its most general, the assembly described herein volatilizes anaerosolizable liquid to form a vapor and/or an aerosol that passesthrough a solid nicotine-containing material so as to produce aninhalable medium that contains one or more constituents, such asnicotine, derived from the solid.

In some assemblies, base-treated nicotine may be included in the solid,nicotine-containing material. The nicotine reacts with the base; thisreaction deprotonates nicotine, increasing its volatility and releasingit from its bound state to provide nicotine in its deprotonated basicform (herein referred to as “deprotonated nicotine” or simply “freenicotine”). As a result, base-treated nicotine will be more readilyvolatilized upon heating. The present inventors have found, however,that inhalable aerosols (sometimes referred to herein as “inhalablemedium”) containing free nicotine have a less desirable taste, incomparison to those containing nicotine salts.

In some embodiments, the inhalable aerosol of the assembly may haveimproved sensory qualities, such as taste. In some embodiments, theinhalable aerosol may have a higher amount of nicotine delivery, and maypromote the extraction of nicotine from a nicotine source, where thenicotine source has been treated with base to raise its pH, incomparison to other inhalable aerosols.

The inventors have determined that by including an acid in theaerosolizable liquid, better tasting inhalable aerosols are produced.The acid in the vapor/aerosol—produced by heating the aerosolizableliquid—reacts with the free nicotine from the solid, nicotine-containingmaterial to provide nicotine in its better tasting, salt form. That is,the acid and free nicotine undergo an acid-base salt formation toproduce nicotine salts in the vapor/aerosol.

It was thought that whilst the use of an acidic aerosol/vapor wouldimprove the taste, it was expected that some reduction in the overallnicotine delivery would be observed as less volatile nicotine saltswould form in the solid, nicotine-containing material, upon contact withthe acidic vapor/aerosol.

Surprisingly, the inventors found that including an acid in theaerosolizable liquid of an assembly actually increases the overallnicotine delivery during use, in comparison to a neutral aerosolizableliquid. Without being limited by theory, it is thought that the affinitybetween the free nicotine and the acid in the vapor/aerosol may draw orextract the nicotine out of the solid, nicotine-containing material. Itis thought that this extraction occurs at a rate that is faster than therate of formation of nicotine salt in the solid. Hence, an inhalableaerosol with improved taste and higher nicotine content may be provided.Using an acidic vapor/aerosol may also allow for a higher overall amountof nicotine to be extracted from the solid.

Solid, Nicotine-Containing Material

In some cases, the invention provides an assembly for generating aninhalable medium or a cartridge for use in an assembly for generating aninhalable medium, wherein the assembly or cartridge includes a solid,nicotine-containing material (herein referred to as “nicotine source” orsimply “solid”).

The nicotine source has a pH of at least 7. In some cases, the nicotinesource has a pH of from 8 to 9.5, of 8.2 to 9.3, of 8.3 to 9.2, of 8.4to 9.1. Suitably, the pH may be of from 8.5 to 9, or may be 8.5. Thisallows for the nicotine in the solid, nicotine-containing material to beprovided in its deprotonated basic form (as free nicotine), therebyincreasing the volatility of the nicotine so that it is more readilyvolatilized on heating.

In some cases, the pH of the nicotine source is selected such that thereis a difference between the pH of the nicotine source and the pH of theaerosolizable liquid of from 3 to 5.5, of 3.5 to 5, of 3.7 to 4.8,suitably from 4.1 to 4.2, suitably from 3.6 to 3.8. Without beinglimited by theory, it is thought that a larger pH difference will resultin higher affinity between the acidic vapor/aerosol and the freenicotine, thereby increasing the rate of extraction, to provide a higheramount of nicotine delivery in the inhalable medium.

The nicotine source may have been treated to raise its pH—the pHmeasured according to the CORESTA protocol for measuring the pH oftobacco, CORESTA Recommended Method No. 69 (CRM-69). An example methodof pH-treatment may comprise the addition of a solution of base to thenicotine source. The solution of base may, in some cases, comprise anaqueous solution of sodium hydroxide, potassium hydroxide, calciumhydroxide, sodium hydrogen carbonate, potassium hydrogen carbonate,calcium hydrogen carbonate, sodium carbonate, potassium carbonate,calcium carbonate or mixtures thereof, or other GRAS water-solublebases, for example.

In some cases, the nicotine source comprises tobacco material. In somecases, the nicotine source is tobacco material. This may provide theinhalable medium with tobacco flavors.

As used herein, the term “tobacco material” refers to any materialcomprising tobacco or derivatives thereof. The term “tobacco material”may include one or more of tobacco, tobacco derivatives, expandedtobacco, reconstituted tobacco or tobacco substitutes. The tobaccomaterial may comprise one or more of ground tobacco, tobacco fiber, cuttobacco, extruded tobacco, tobacco stem, reconstituted tobacco,agglomerated tobacco, spheronized tobacco and/or tobacco extract.

The tobacco used to produce tobacco material may be any suitabletobacco, such as single grades or blends, cut rag or whole leaf,including Virginia and/or Burley and/or Oriental. It may also be tobaccoparticle ‘fines’ or dust, expanded tobacco, stems, expanded stems, andother processed stem materials, such as cut rolled stems. The tobaccomaterial may be a ground tobacco or a reconstituted tobacco material.The reconstituted tobacco material may comprise tobacco fibers, and maybe formed by casting, a Fourdrinier-based paper making-type approachwith back addition of tobacco extract, or by extrusion.

In some cases, the nicotine source may be porous, such that an aerosoland/or vapor can pass through the solid nicotine source. This provides ahigh contact area for the nicotine source to contact the aerosol and/orvapor. Thus, components of the nicotine source are efficiently entrainedin the aerosol/vapor.

The nicotine source may additionally comprise flavorings and/or aerosolgenerating agents. As used herein, the terms “flavor” and “flavorant”refer to materials that, where local regulations permit, may be used tocreate a desired taste or aroma in a product for adult consumers.

In some cases, the nicotine source may be provided in one of twochambers of a cartridge as described herein.

In some cases, the nicotine source may be provided in anicotine-containing pod, configured for use in an assembly for use ingenerating an inhalable medium, as part of a kit as described herein.

Aerosolisable Liquid

In some cases, the invention provides an assembly for generating aninhalable medium or a cartridge for use in an assembly for generating aninhalable medium, wherein the assembly or cartridge includes anaerosolizable liquid (sometimes herein referred to as simply “liquid”).

The aerosolizable liquid may, in some cases, comprise a gel and/orliquid. Suitably, the aerosolizable liquid comprises, substantiallyconsists of, or consists of a liquid.

The aerosolizable liquid may comprise liquids that are conventionallyused in e cigarette or Hybrid assemblies. In some cases, theaerosolizable liquid may comprise flavorings and/or aerosol-generatingagents, including but not limited to propylene glycol and/or glycerol.The aerosolizable liquid is typically volatilized at around 100-300° C.,suitably at around 150-250° C. In some cases, the aerosolizable liquiddoes not contain nicotine.

The aerosolizable liquid comprises an acid, such that the aerosolizableliquid may have a pH of from at least 2 to 7, or from about 2.5 to about5. In some embodiments, the pH of the aerosolizable liquid is from 4 to5. In some cases, the liquid has a pH of from 4.1 to 4.9, of 4.2 to 4.8,suitably of from 4.3 to 4.8, suitably 4.37, suitably 4.8.

In some cases, the liquid has a pH of from 2, 2.1, 2.2, 2.3, 2.4, 2.5,2.6, 2.7, 2.8, 2.9, 3, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9 orfrom 4 and of up to 6.9, 6.8, 6.7, 6.6, 6.5, 6.4, 6.3, 6.2, 6.1, 6, 5.9,5.8, 5.7, 5.6, 5.5, 5.4, 5.3, 5.2, 5.1, 5, 4.9, 4.8, 4.7, 4.6, 4.5, 4.4,4.3, 4.2, 4.1 or up to 4. Without being limited by theory, it is thoughtthat this results in an affinity between the free nicotine from thenicotine source and the acid in the vapor/aerosol; the affinity is suchthat the vapor/aerosol may draw or extract the nicotine out of thenicotine source. It is thought that a lower pH of the aerosolizableliquid will result in a higher affinity between the free nicotine andthe aerosolizable liquid, and thus may increase the extraction rate.

The pH of the aerosolizable liquid is dependent upon various properties,such as pKa or concentration of the acid, and the acidity or basicity ofany other components in the aerosolizable liquid.

In some cases, the pH of the aerosolizable liquid is selected such thatthere is a difference between the pH of the nicotine source and the pHof the aerosolizable liquid of from 3 to 5.5, of 3.5 to 5, of 3.7 to4.8, suitably from 4.1 to 4.2, suitably from 3.6 to 3.8. Without beinglimited by theory, it is thought that a larger pH difference will resultin higher affinity between the acidic vapor/aerosol and the freenicotine, thereby increasing the extraction rate to provide a higheramount of nicotine delivery in the inhalable medium.

In some cases, any characteristic of the aerosolizable liquid may bealtered or selected in order to increase affinity of the liquid with thefree “deprotonated” nicotine in the nicotine source, including but notlimited to dipole moment, polarity, and vapor pressure. For example, ahigher dipole moment, polarity or vapor pressure may increase affinityof the liquid with the free “deprotonated” nicotine in the nicotinesource. The addition of an acid may alter the polarity and vaporpressure characteristics of the aerosolizable liquid, which areimportant for the desired effect in this invention. Further, a non-acidsubstance that can alter polarity (increasing more positive dipole inthe liquid); this may lead to similar effect like addition of acid.

ACID

Any acid that is suitable for the protonation of nicotine may be used inthe aerosolizable liquid. Examples of acids include, but are not limitedto, inorganic acids such as hydrochloric, hydrobromic, or sulfuric acid,and organic acids including saturated and unsaturated aliphatic acids,saturated and unsaturated alicyclic acids, aromatic acids (includingheterocyclic aromatic), polycarboxylic acids, hydroxy, alkoxy, keto, andoxo acids, thioacids, amino acids, and each of the preceding optionallysubstituted with one or more heteroatoms, including but not limited tohalogens. In some cases, the acid is a carboxylic acid, suitably benzoicacid. In some cases, the carboxylic acid is a hydroxyl acid, suitablylactic acid. In some cases, the acid is selected from the groupconsisting of benzoic acid, lactic acid, and combinations thereof. Theselected acid may protonate the free nicotine, and promote acid-basesalt formation upon contact of the aerosol/vapor with the nicotinesource, thereby providing nicotine salts. This promotes extraction ofthe nicotine from the nicotine source to increase nicotine delivery ofthe assembly, and improves the taste of nicotine in the inhalablemedium.

In some cases, the acid selected has a pKa greater than 0.5, 1, 1.5, 2,2.5, 3, or greater than 3.5, or suitably of from 3.7 to 4.3. Withoutbeing limited by theory, it is thought that this promotes the acid-basesalt formation of free nicotine to improve the flavor and the amount ofnicotine delivery by the inhalable medium; a lower pKa, or a strongeracid, for the same pH of a nicotine source, will increase the affinitybetween the aerosolizable liquid and the free nicotine, and may promoteextraction of nicotine from the nicotine source to provide a highernicotine delivery in the inhalable medium during use.

In some cases, the acid has a pKa of greater than 3, or of from 3.7 to4.3, and provides an aerosolizable liquid with a pH of from 4 to 5, of4.1 to 4.9, of 4.2 to 4.8, suitably from 4.3 to 4.8, suitably 4.37,suitably 4.8. Thus, in some embodiments, this promotes the acid-basesalt formation of free nicotine to provide improved flavor and increasethe amount of nicotine delivery by the inhalable medium during use.

In some cases, the aerosolizable liquid comprises an acid with a vaporpressure at 25° C. of from 0.05 Pa to 3 kPa, from 0.1 Pa to 2.5 kPa,from 0.1 Pa to 2 kPa, from 0.1 Pa to 1.5 kPa, from 0.1 Pa to 1 kPa, from0.1 Pa to 750 Pa, from 0.1 to 500 Pa, from 0.1 to 250 Pa, from 0.1 to100 Pa, from 0.1 to 90 Pa, from 0.1 to 80 Pa, from 0.1 to 70 Pa, from0.1 to 60 Pa, from 0.1 to 50 Pa, from 0.1 to 40 Pa, from 0.1 to 30 Pa,from 0.1 to 20 Pa, from 0.1 to 11 Pa, suitably from 0.1 to 0.2, suitablyfrom 9 to 11 Pa. An acid with a higher vapor pressure at 25° C. will bemore volatile. Thus, more acid may be present in the aerosol/vapor andthis may further increase the rate of extraction of free nicotine fromthe nicotine source during use.

In some cases, the aerosolizable liquid comprises an acid in an amountof from 0.001 to 5% by weight. In some embodiments, the aerosolizableliquid comprises an acid in an amount of at least 0.01%, 0.1%. 0.5%,0.6%, 0.7%, 0.8% 0.9% or at least 1% acid. In some embodiments, theaerosolizable liquid comprises as acid in an amount of up to 4.5%, 4%,3.5%, 3%, 2.5%, 2%, 1.5%, 1%, 0.5%, 0.1% or up to 0.01% by weight.Including the acid in the aerosolizable liquid at higher concentrationswill increase the acidity and lower the pH of the aerosolizable liquid.Without being limited by theory, it is thought that a higher acidity ofthe aerosolizable liquid may result in it having a higher affinity tothe free nicotine in the nicotine source, thereby facilitating theextraction of nicotine to increase the amount of nicotine delivery bythe inhalable medium during use.

In some cases, the aerosolizable liquid comprising an acid may beprovided in one of two chambers of a cartridge as described herein.

In some cases, the aerosolizable liquid comprising an acid may beprovided in a liquid pod, configured for use in an assembly for use ingenerating an inhalable medium, as part of a kit as described herein.

In some cases, the acid may be selected such that the conjugateacid-base salt formed upon reaction with the free nicotine in theaerosol/vapor has a high volatility (i.e. has a high vapor pressure).This may further increase the amount of nicotine delivery in theinhalable medium.

In some embodiments, the conjugate acid-base will have a vapor pressuresimilar to or slightly less than that of the acid used. Conjugateacid-base formation is one mechanism of elevating vapor pressure.

Assembly

The assembly according to some examples of the invention may beconfigured such that in use, liquid volatilized by the heater passes, inthe form of at least one of a vapor and an aerosol, through the solidnicotine source to thereby entrain one or more components from thenicotine source to produce the inhalable medium. In some cases, theinhalable medium passes out of an outlet.

The assembly may comprise components such as a first chamber (referredto herein as the “liquid chamber”) for housing the aerosolizable liquid,and a second chamber (referred to herein as the “solid chamber”) forhousing the solid, nicotine-containing material. The assembly mayfurther comprise an outlet, and a flow path between the chambers and theoutlet.

When the vapor/aerosol passes through the nicotine source, it iscontacted with the nicotine source to entrain one or more componentsthereof. Once entrained in the vapor/aerosol, the one or more componentsfrom the nicotine source may undergo reactions with components in thevapor/aerosol. For example, acid-base salt formation reactions mayoccur. Without being bound by theory, it is thought that the acid-basesalt formation reaction in the vapor/aerosol occurs at a higher ratethan the acid-base salt formation reaction in the solid. The use of anacidic vapor/aerosol may result in a higher amount of nicotine to beextracted or drawn out of the tobacco, when compared to a vapor/aerosolwith a neutral pH.

In some embodiments, the assembly heats the nicotine source in use,encouraging release of components thereof into the inhaled medium. Inother embodiments, the assembly heats both the nicotine source and theaerosolizable liquid. Suitably, the assembly may be configured such thatthe heater only heats the aerosolizable liquid directly and the nicotinesource is heated by warmth carried in the vapor/aerosol formed from theaerosolizable liquid (thereby volatilizing components of the nicotinesource that are then entrained in the vapor/aerosol flow). That is, theassembly is configured such that it directly heats the aerosolizableliquid, but does not directly heat the solid, nicotine-containingmaterial.

In some cases, the invention provides a cartridge for use in an assemblyfor generating an inhalable medium, the cartridge comprising anaerosolizable liquid comprising an acid in a first chamber, the liquidcorresponding to the liquid as described hereinabove, and a solid,nicotine-containing material in a second chamber, the solid,nicotine-containing material corresponding to the nicotine sourcedescribed hereinabove. The cartridge is configured such that in use, avapor and/or an aerosol generated from the aerosolizable liquid passesthrough the second chamber containing the nicotine source and entrainsone or more constituents of the nicotine source. Suitably, the cartridgemay be adapted for use in the assembly for generating an inhalablemedium described herein.

In some embodiments, the assembly comprises a cooler or cooling zonedownstream of the heater and upstream of the second chamber containing anicotine source, the cooler or cooling zone being arranged to coolvaporized material to form an aerosol of liquid droplets that, in use,pass through the nicotine source in the second chamber. In someembodiments, the cooler may be arranged in effect to act as a heatexchanger, allowing for recovery of heat from the vapor and/or aerosol.The recovered heat may be used, for example, to pre-heat the nicotinesource and/or to assist in heating the aerosolizable liquid.

In an embodiment, the assembly is battery-operated.

In an embodiment, the or each heater is an electrically resistiveheater.

In an embodiment, the heater is puff actuated. That is, the assemblyincludes a puff-detector and only heats the aerosolizable liquid ondetection of a puff. This means that vapor/aerosol forms in the assemblyonly during puffs.

In an embodiment, the first and/or second chamber is removable. Thefirst and/or second chamber may be in the form of a pot or the like(that in some embodiments may be annular for example), and/or anabsorbent wadding or the like. The first and/or second chamber may ineffect be a disposable item that is replaced as a whole after use. As analternative, the arrangement may be such that the user removes the firstand/or second chamber from the assembly, replaces used material or topsup the material in the first and/or second chamber, and then places itback in the assembly.

In some cases, the first and/or second chamber may be non-removable fromthe assembly. In such an embodiment, the user may just replace usedmaterial or top up material in a chamber after use as necessary.

In some cases, the first and second chamber are an integral unit. Insome cases, the integral unit is a cartridge that can be removed fromthe assembly.

In some cases, the first and/or second chamber is removable from theassembly. The first and/or second chamber may be, for example, in theform of a cartridge or the like which contains the nicotine sourcebefore use. The second chamber containing the nicotine source may ineffect be a disposable item, which is replaced as a whole after use. Asan alternative, the arrangement may be such that the user removes thesecond chamber from the assembly, replaces used material in the secondchamber, and then places the second chamber back in the assembly.

The invention also provides a kit comprising an aerosol-generatingassembly according to embodiments of the invention. The kit comprises(i) a liquid pod containing an aerosolizable liquid according to theembodiments described herein, (ii) a nicotine-containing pod containinga solid, nicotine-containing material according to the embodimentsdescribed herein. Features described hereinabove in relation to theassembly are explicitly disclosed in combination with the kit aspect ofthe invention. Thus, for example, the assembly may include one or morepuff actuators, a cooling element or cooling zone, actuation means suchas a button, further heaters, a pump for the wetting agent, and so on.

The invention also provides the use of an acidic vapor and/or aerosol toextract nicotine from a solid, nicotine-containing material having a pHof more than 7, wherein the rate of nicotine extraction exceeds the rateof nicotine-salt formation in the solid, nicotine-containing material,thereby providing an increased nicotine content in the vapor and/oraerosol as compared to using a neutral vapor and/or aerosol.

Examples of cartridges, liquid pods, nicotine-containing pods andassemblies for generating an inhalable medium according to someembodiments of the invention will now be described, with reference tothe accompanying drawings.

Referring to FIG. 1 , there is shown an example of an assembly 1 forgenerating an inhalable medium. In broad outline, the assembly 1volatilizes an aerosolizable liquid to form a vapor and/or an aerosolwhich passes through a nicotine source so as to produce an inhalablemedium that contains one or more components derived from the nicotinesource.

In this respect, first it may be noted that, in general, a vapor is asubstance in the gas phase at a temperature lower than its criticaltemperature, which means that for example the vapor can be condensed toa liquid by increasing its pressure without reducing the temperature. Onthe other hand, in general, an aerosol is a colloid of fine solidparticles or liquid droplets, in air or another gas. A “colloid” is asubstance in which microscopically dispersed insoluble particles aresuspended throughout another substance.

Returning to FIG. 1 , the assembly 1 of this example has a generallyhollow cylindrical outer housing 2. The housing 2 has an open end 3. Inthis example, a tubular mouthpiece 4 is provided in the open end 3. Themouthpiece 4 in this example is removable by a user from the housing 2.An O¬ring or other seal 5 assists in sealing the mouthpiece 4 in thehousing 2. At or towards the other end 6 of the housing 2 is a battery 7for powering various components of the assembly 1, as will be discussedfurther below. The battery 7 may be a rechargeable battery or adisposable battery. A controller 8 is also provided in the housing 2 forcontrolling the operation of various components of the assembly 1, aswill be discussed further below.

The housing 2 has a chamber 9 (sometimes referred to herein as “liquidchamber”) for holding or containing an aerosolizable liquid (sometimesreferred to herein as simply “liquid”) 10. The liquid 10 corresponds tothe liquid described hereinabove and may have a pH of from 4 to 5,and/or may comprise an acid with a pKa greater than 3, for example.Various different forms for the liquid chamber 9 may be used. In theexample of FIG. 1 , the liquid chamber 9 is in the form of an annularchamber 9 provided in the housing 2 between the open end 3 and the otherend 6. In this particular example, the housing 2 is in two parts, afirst part 2 a being towards the open end 3 and a second part 2 btowards the other end 6. The first and second parts 2 a, 2 b of thehousing 2 may connect to each other via a screw thread, a bayonetfitting or the like. In use, a user can separate the first and secondparts 2 a, 2 b of the housing 2 to allow the aerosolizable liquid 10 tobe replenished or replaced as necessary. Alternatively, the mouthpiece 4can be removed to provide access to the liquid chamber 9. It will beunderstood however that other arrangements are possible. For example,the liquid 10 may be provided in a discrete annular pot-like liquidchamber, which can be removed as a whole from the housing 2. Such adiscrete liquid chamber may be disposable so that the user replaces theliquid 10 by fitting a new liquid chamber with liquid 10 in the housing2. Alternatively, such a chamber may be reusable. In such a case, theuser may replenish or replace liquid 10 in the liquid chamber whilst ithas been removed from the housing 2 and then replace the refilled liquidchamber in the housing 2. It will be understood that the housing 2 neednot be in two parts and that other arrangements enabling access for theuser may be provided, for example, to enable refilling in situ.

A heater 11 is provided generally centrally of the housing 2, that is,centrally along the length and width of the housing 2 in this example.In this example, the heater 11 is powered by the battery 7 and istherefore electrically connected to the battery 7. The heater 11 may bean electrically resistive heater, including for example a nichromeresistive heater, a ceramic heater, etc. The heater 11 may be forexample a wire, which may for example be in the form of a coil, a plate(which may be a multi-layer plate of two or more different materials,one or more of which may be electrically conductive and one or more ofwhich may be electrically non-conductive), a mesh (which may be woven ornon-woven for example, and which again may be similarly multi-layer), afilm heater, etc. Other heating arrangements may be used, includingnon-electrical heating arrangements.

This heater 11 is provided for volatilizing the liquid 10. In theexample shown, an annular wick 12 surrounds the heater 11 and is in(thermal) contact with the heater 11. The outermost surface of theannular wick 12 is in contact with liquid 10 contained in the liquidchamber 9. The wick 12 is generally absorbent and acts to draw in liquid10 from the liquid chamber 9 by capillary action. The wick 12 ispreferably non-woven and may be for example a cotton or wool material orthe like, or a synthetic material, including for example polyester,nylon, viscose, polypropylene or the like. Whilst this will be describedmore fully below, it may be noted here that in use, liquid 10 drawn intothe wick 12 is heated by the heater 11. The liquid 10 may be volatilizedso as to produce an aerosol of liquid droplets or sufficiently heated toproduce a vapor. The aerosol and/or vapor so produced exits the wick 12and passes towards the mouthpiece 4 as shown by the arrows A under theaction of the user drawing on the mouthpiece 4. The heater 11 and wick12 may be provided as a single, effectively integral item, sometimesreferred to as an “atomizer”, such that the heating and wicking iseffectively carried out by a single unit.

The housing 2 further contains a chamber (sometimes referred to hereinas “solid chamber”) 13 which holds or contains a solid,nicotine-containing material (referred to herein as “nicotine source”)14 in the assembly 1. The nicotine source 14 corresponds to the nicotinesource described hereinabove, is base-treated, and may have a pH of from8 to 9.5, for example. In use, a user can access the solid chamber 13 toreplace or replenish the nicotine source 14 through the open end 3 ofthe housing 2 by removing the mouthpiece 4 and/or by separating the twoparts 2 a, 2 b of the housing 2. Various different forms for the solidchamber 13 may be used. For example, the solid chamber 13 may be a tubewhich is completely open at both ends and which contains the nicotinesource 14. As another example, the solid chamber 13 may be a tube, whichhas one or more end walls, which have through holes through which avapor and/or aerosol can pass. The solid chamber 13 may remain in situwithin the housing 2 whilst the user removes and replaces the nicotinesource 14. Alternatively, the solid chamber 13 containing the nicotinesource 14 may be a discrete item, which in use is inserted into andremoved from the housing 2 as a whole. A removable solid chamber 13 ofthis type may be disposable so that the user replaces the nicotinesource 14 by fitting a new solid chamber 13 containing a fresh nicotinesource 14 into the housing 2. As an alternative, the solid chamber 13may be reusable. In such a case, the user may replace the nicotinesource 14 in the solid chamber 13 whilst the solid chamber 13 has beenremoved from the housing 2 and then replace the refilled solid chamber13 in the housing 2. In yet another example, the solid chamber 13 maycomprise clips or the like provided internally of the housing 2 andwhich retain the nicotine source 14 in position. In some examples, thenicotine source 14 could simply fit snugly within the solid chamber 13.As another alternative, the chamber 9 for containing the liquid 10 mayitself be arranged to support or carry the nicotine source 14. Forexample, the liquid chamber 9 may have one or more clips, a tube, or thelike for receiving and holding the nicotine source 14 in position. Sucha dual function liquid chamber 9/solid chamber 13 for both containingthe liquid 10 and receiving the nicotine source 14 may be in the form ofa cartridge or the like and may be a disposable item or may bere-useable, with the liquid 10 and nicotine source 14 being replaced ortopped up by the user as required. In some cases, it may be that theuser only needs to top up or replace the nicotine source 14 from time totime, with sufficient liquid 10 being provided for several uses. Oncethe liquid 10 has been consumed, the user disposes of the dual functionliquid chamber 9/solid chamber 13 and uses a new one. Likewise, it maybe that the user only needs to top up or replace the liquid 10 from timeto time, with sufficient nicotine source 14 being provided for severaluses. Once the nicotine source 14 has been consumed, the user disposesof the dual function liquid chamber 9/solid chamber 13 and uses a newone. Specific examples of dual function liquid chambers/solid chambersare discussed further below.

The nicotine source 14 is located in the housing 2 downstream of thelocation where the aerosol and/or vapor is produced from the liquid 10and upstream of the open end 3 of the housing 2 and the mouthpiece 4. Inthis particular example, the nicotine source 14 is effectively providedin the same portion or chamber of the housing 2 as the wick 12. Theaerosol and/or vapor produced from the liquid 10 exits the wick 12 andpasses as shown by the arrows A towards the nicotine source 14 under theaction of the user drawing on the mouthpiece 4. In particularembodiments, the nicotine source 14 is porous so that the aerosol and/orvapor passes through the nicotine source 14 and then through the openend 3 of the housing 2 and the mouthpiece 4.

In some embodiments, the nicotine source 14 and/or its chamber 13 arearranged so that there is no air gap between the nicotine source14/solid chamber 13 and the interior of the housing 2 so that theaerosol and/or vapor flows entirely through the nicotine source 14.

The liquid 10 is suitably a liquid that is volatilizable at reasonabletemperatures, preferably of from 100-300° C. or more particularly around150-250° C., as that helps to keen down the power consumption of theassembly 1. Suitable materials include those conventionally used in ecigarette assemblies, including for example propylene glycol andglycerol (also known as glycerine). The liquid 10 corresponds to theliquid described hereinabove and may have a pH of from 4 to 5, and/ormay comprise an acid with a pKa greater than 3, for example.

The nicotine source 14 imparts a flavor to the aerosol and/or vaporproduced from the liquid 10 as the aerosol and/or vapor passes throughthe nicotine source 14. As the acidic aerosol and/or vapor passesthrough and over the nicotine source 14, the hot aerosol and/or vaporentrains organic and other compounds or constituents from the nicotinesource 14 that lend the nicotine source its organoleptic properties,thus imparting the flavor to the aerosol and/or vapor as it passes tothe mouthpiece 4. In particular, the free “deprotonated” nicotine in thenicotine source 14 undergoes acid-base salt formation with the acidicvapor and/or aerosol from the liquid 10. In this way, nicotine may bedrawn out or extracted by the acidic vapor and/or aerosol from thenicotine source 14 to increase the amount of nicotine delivery in theinhalable medium. Furthermore, by passing the acidic vapor/aerosolthrough and over the nicotine source 14, nicotine is provided in itsbetter tasting, salt form.

The assembly 1 provides nicotine for the user. The nicotine is obtainedfrom the nicotine source 14, or it may be provided as a coating or thelike on the nicotine source 14, or a combination of these. Likewise,flavorings may be added to the nicotine source 14 and/or to the liquid10.

In the example shown in FIG. 1 , the only heat source for heating thenicotine source 14 in the assembly 1, which is required so as togenerate the organic and other compounds or constituents from thenicotine source 14, is the hot aerosol and/or vapor produced fromheating the liquid 10.

Referring now to FIG. 2 , there is shown another example of an assemblyfor generating an inhalable medium. In the following description and inFIG. 2 , components and features that are the same as or similar to thecorresponding components and features of the example described withreference to FIG. 1 have the same reference numeral but increased by200. For the sake of brevity, the description of those components andfeatures will not be repeated in its entirety here. It will beunderstood that the arrangements and alternatives, etc. described abovein relation to the example of FIG. 1 are also applicable to the exampleof FIG. 2 . Again, in broad outline, the assembly 201 of FIG. 2 heats aliquid to form a vapor and/or an aerosol which passes through a nicotinesource 214 so as to produce an inhalable medium that contains one ormore components derived from the nicotine source 214.

The assembly 201 of this example has a generally hollow cylindricalouter housing 202 with an open end 203 and a tubular mouthpiece 204. Themouthpiece 204 in this example is removable by a user from the housing202 and an O¬ring or other seal 205 assists in sealing the mouthpiece204 in the housing 202. A battery 207 for powering various components ofthe assembly 201 and a controller 208 are provided at or towards theother end 206 of the housing 202. The housing 202 of this example is intwo parts, a first part 202 a being towards the open end 203 and asecond part 202 b towards the other end 206.

The housing 202 has a chamber (sometimes referred to herein as “liquidchamber”) 209 for holding or containing an aerosolizable liquid(sometimes referred to herein as simply “liquid”) 210. The liquid 210corresponds to the liquid described hereinabove and may have a pH offrom 4 to 5, and/or may comprise an acid with a pKa greater than 3, forexample. The liquid chamber 209 may be of any of the types describedabove in relation to the example of FIG. 1 . A heater 211 is providedgenerally centrally (lengthwise and widthwise) of the housing 202 forvolatilizing the liquid 210. In this example, the heater 211 is poweredby the battery 207 and is therefore electrically connected to thebattery 207. The heater 211 may be an electrically resistive heater, aceramic heater, etc. The heater 211 may be for example a wire, which mayfor example be in the form of a coil, a plate (which may be amulti-layer plate of two or more different materials, one or more ofwhich may be electrically conductive and one or more of which may beelectrically non-conductive), a mesh (which may be woven or non-wovenfor example, and which again may be similarly multi-layer), a filmheater, etc. Other heating arrangements may be used, including inductiveheating arrangements or non-electrical heating arrangements. An annularwick 212 surrounds the heater 211 and is in (thermal) contact with theheater 211. The outermost surface of the annular wick 212 is in contactwith liquid 210 contained in the liquid chamber 209. The liquid 210 maybe heated so as to produce an aerosol of liquid droplets or sufficientlyheated to produce a vapor. The aerosol and/or vapor so produced exitsthe wick 212 and passes towards the mouthpiece 204 as shown by thearrows A under the action of the user drawing on the mouthpiece 204. Theheater 211 and wick 212 may be provided as a single, effectivelyintegral item such that the heating and wicking is effectively carriedout by a single unit.

The housing 202 further contains a chamber (sometimes referred to hereinas “solid chamber) 213 which holds or contains a nicotine source 214 inthe assembly 201. The nicotine source 214 corresponds to the nicotinesource described hereinabove, is base-treated, and may have a pH of from8 to 9.5, for example. The solid chamber 213 may be of any of the typesdescribed above in relation to the example of FIG. 1 . The nicotinesource 214 is located in the housing 202 downstream of the locationwhere the aerosol and/or vapor is produced from the liquid 210 andupstream of the open end 203 of the housing 202 and the mouthpiece 204.In this particular example, the nicotine source 214 is effectivelyprovided in the same portion or chamber of the housing 202 as the wick212. The aerosol and/or vapor produced from the liquid 210 exits thewick 212 and passes as shown by the arrows A towards the nicotine source214 under the action of the user drawing on the mouthpiece 204. Inparticular embodiments, the nicotine source 214 is porous so that theaerosol and/or vapor passes through the nicotine source 214 and thenthrough the open end 203 of the housing 202 and the mouthpiece 204.

In some embodiments, the nicotine source 214 and/or its chamber 213 arearranged so that there is no air gap between the nicotine source214/chamber 213 and the interior of the housing 202 so that the aerosoland/or vapor flows entirely through the nicotine source 214. As theaerosol and/or vapor passes through and over the nicotine source 214,the hot aerosol and/or vapor entrains organic and other compounds orconstituents from the nicotine source 214 that lend the nicotine sourceits organoleptic properties, thus imparting the flavor to the aerosoland/or vapor as is passes to the mouthpiece 204. In particular, the free“deprotonated” nicotine in the nicotine source 214 undergoes acid-basesalt formation with the acidic vapor and/or aerosol from the liquid 210.In this way, nicotine may be drawn out or extracted by the acidic vaporand/or aerosol from the nicotine source 214 to increase the amount ofnicotine delivery in the inhalable medium. Furthermore, by passing theacidic vapor/aerosol through and over the nicotine source 214, nicotineis provided in its better tasting, salt form.

The liquid chamber 209 for containing the liquid 210 may itself bearranged to support or carry the nicotine source 214. For example, theliquid chamber 209 may have one or more clips, a tube, or the like forreceiving and holding the nicotine source 214 in position. Such a dualfunction liquid chamber 209/solid chamber or receptacle 213 for bothcontaining the liquid 210 and receiving the nicotine source 214 may bein the form of a cartridge or the like and may be a disposable item ormay be re-useable, with the liquid 210 and nicotine source 214 beingreplaced or topped up by the user as required. In some cases, it may bethat the user only needs to top up or replace the nicotine source 214from time to time, with sufficient liquid 210 being provided for severaluses. Once the liquid 210 has been consumed, the user disposes of thedual function liquid chamber 209/solid chamber 213 and uses a new one.Likewise, it may be that the user only needs to top up or replace theliquid 210 from time to time, with sufficient nicotine source 214 beingprovided for several uses. Once the nicotine source 214 has beenconsumed, the user disposes of the dual function liquid chamber209/solid chamber 213 and uses a new one.

In the example assembly 201 of FIG. 2 , a second heater 215, such as anoven heater, is provided in thermal contact with the nicotine source 214to pre-heat the nicotine source 214 and/or provide additional heat tothe nicotine source 214 throughout use of the assembly 201. Thisencourages release of constituents from the nicotine source 214 as thevapor and/or aerosol passes through the nicotine source 214 in use. Theamount of heated liquid 210 to achieve desirable heating of the nicotinesource 214 may be reduced. The second heater 215 may be an electricallyresistive heater, a ceramic heater, etc., powered by for example thebattery 207. The second heater 215 may be for example a wire, which mayfor example be in the form of a coil, a plate (which may be amulti-layer plate of two or more different materials, one or more ofwhich may be electrically conductive and one or more of which may beelectrically non-conductive), a mesh (which may be woven or non-wovenfor example, and which again may be similarly multi-layer), a filmheater, etc. The second heater 215 may be an inductive heater powered byfor example the battery 207. Nicotine source 214 may include materialssusceptible to inductive heating. Other heating arrangements may be usedfor the second heater 215, including non-electrical heatingarrangements.

In the example assembly 201 of FIG. 2 , the heater 215 for heating thenicotine source 214 is provided externally of the nicotine source 214and heats the nicotine source 214 by heat conduction from the exteriorof the nicotine source 214. The heater 215 in this example is generallycylindrical. The heater 215 may in effect be an integral part of theassembly 201 and be provided as part of the housing 202. As analternative, the heater 215 may be provided integrally with the solidchamber 213 which holds or contains the nicotine source 214. In thisalternative, in the case that the solid chamber 213 is disposable, theheater 215 will be replaced when a new solid chamber 213 with freshnicotine source is loaded into the assembly 201 by the user.

Referring now to FIG. 3 , there is shown another example of an assemblyfor generating an inhalable medium. In the following description and inFIG. 3 , components and features that are the same as or similar to thecorresponding components and features of the example described withreference to FIG. 1 have the same reference numeral but increased by300. For the sake of brevity, the description of those components andfeatures will not be repeated in its entirety here. It will beunderstood that the arrangements and alternatives, etc. described abovein relation to the examples of FIG. 1 and FIG. 2 are also applicable tothe example of FIG. 3 . Again, in broad outline, the assembly 301 ofFIG. 3 heats a liquid to form a vapor and/or an aerosol which passesthrough a nicotine source 314 so as to produce an inhalable medium thatcontains one or more constituents derived from the nicotine source 314.

The assembly 301 of this example again has a generally hollowcylindrical outer housing 302 with an open end 303 and a tubularmouthpiece 304, which is removable by a user from the housing 302.O¬ring or other seal 305 assists in sealing the mouthpiece 304 in thehousing 302. A battery 307 for powering various components of theassembly 301 and a controller 308 are provided at or towards the otherend 306 of the housing 302. The housing 302 of this example is again intwo parts, a first part 302 a being towards the open end 303 and asecond part 302 b towards the other end 306.

The housing 302 has a chamber (sometimes referred to herein as “liquidchamber”) 309 for holding or containing an aerosolizable liquid(sometimes referred to herein as simply “liquid”) 310. The liquid 310corresponds to the liquid described hereinabove and may have a pH offrom 4 to 5, and/or may comprise an acid with a pKa greater than 3, forexample. The liquid chamber 309 may be of any of the types describedabove in relation to the examples of FIGS. 1 and 2 . A heater 311 isprovided generally centrally of the housing 302 for heating the liquid310. The heater 311 may be any of the types described above. In thisexample, the heater 311 is powered by the battery 307 and is thereforeelectrically connected to the battery 307. An annular wick 312 surroundsthe heater 311 and is in (thermal) contact with the heater 311. Theoutermost surface of the annular wick 312 is in contact with liquid 310contained in the liquid chamber 309. The liquid 310 may be heated so asto produce an aerosol of liquid droplets or sufficiently heated toproduce a vapor. The aerosol and/or vapor so produced exits the wick 312and passes towards the mouthpiece 304 as shown by the arrows A under theaction of the user drawing on the mouthpiece 304. The heater 311 andwick 312 may be provided as a single, effectively integral item suchthat the heating and wicking is effectively carried out by a singleunit.

The housing 302 further contains a chamber (sometimes referred to hereinas “solid chamber”) 313 which holds or contains a nicotine source 314 inthe assembly 301. The nicotine source 314 corresponds to the nicotinesource described hereinabove, is base-treated, and may have a pH of from8 to 9.5, for example. The solid chamber 313 may be of any of the typesdescribed above in relation to the examples of FIGS. 1 and 2 . (In theexample shown in FIG. 3 , the solid chamber 313 is in the form of a tubewhich has end walls 316 which have through holes 317 through which avapor and/or aerosol can pass, which was mentioned as an option above.)The nicotine source 314 is located in the housing 302 downstream of thelocation where the aerosol and/or vapor is produced from the liquid 310and upstream of the open end 303 of the housing 302 and the mouthpiece304. In this particular example, again, the nicotine source 314 iseffectively provided in the same portion or chamber of the housing 302as the wick 312. The aerosol and/or vapor produced from the liquid 310exits the wick 312 and passes as shown by the arrows A towards thenicotine source 314 under the action of the user drawing on themouthpiece 304. In particular embodiments, the nicotine source 314 isporous so that the aerosol and/or vapor passes through the nicotinesource 314 and then through the open end 303 of the housing 302 and themouthpiece 304.

In some embodiments, the nicotine source 314 and/or its chamber 313 arearranged so that there is no air gap between the nicotine source314/chamber 313 and the interior of the housing 302 so that the aerosoland/or vapor flows entirely through the nicotine source 314. As theaerosol and/or vapor passes through and over the nicotine source 314,the hot aerosol and/or vapor entrains organic and other compounds orconstituents from the nicotine source 314, thus imparting flavor to theaerosol and/or vapor as is passes to the mouthpiece 304. In particular,the free “deprotonated” nicotine in the nicotine source 314 may undergoacid-base salt formation with the acidic vapor and/or aerosol from theliquid 310. In this way, nicotine may be drawn out or extracted by theacidic vapor and/or aerosol from the nicotine source 314 to increase theamount of nicotine delivery in the inhalable medium. Furthermore, bypassing the acidic vapor/aerosol through and over the nicotine source314, nicotine may be provided in its better tasting, salt form.

The chamber 309 for containing the liquid 310 may itself be arranged tosupport or carry the nicotine source 314. For example, the liquidchamber 309 may have one or more clips, a tube, or the like forreceiving and holding the nicotine source 314 in position. Such a dualfunction liquid chamber 309/solid chamber or receptacle 313 for bothcontaining the liquid 310 and receiving the nicotine source 314 may bein the form of a cartridge or the like and may be a disposable item ormay be re-useable, with the liquid 310 and nicotine source 314 beingreplaced or topped up by the user as required. In some cases, it may bethat the user only needs to top up or replace the nicotine source 314from time to time, with sufficient liquid 310 being provided for severaluses. Once the liquid 310 has been consumed, the user disposes of thedual function liquid chamber 309/solid chamber 313 and uses a new one.Likewise, it may be that the user only needs to top up or replace theliquid 310 from time to time, with sufficient nicotine source 314 beingprovided for several uses. Once the nicotine source 314 has beenconsumed, the user disposes of the dual function liquid chamber309/solid chamber 313 and uses a new one.

In the example assembly 301 of FIG. 3 , a second heater 318 is againprovided in thermal contact with the nicotine source 314 to heat thenicotine source 314 to encourage release of constituents from thenicotine source 314 as the vapor and/or aerosol passes through thenicotine source 314 in use. The second heater 318 may be an electricallyresistive heater, a ceramic heater, etc., powered by for example thebattery 307. Other heating arrangements may be used for the secondheater 318, including non-electrical heating arrangements.

In the example assembly 301 of FIG. 3 , the heater 318 for heating thenicotine source 314 is provided internally of the nicotine source 314and heats the nicotine source 314 by heat conduction from the interiorof the nicotine source 314. The heater 318 in this example is generallyin the form of a cylindrical rod located along the central longitudinalaxis of the nicotine source 314. In other arrangements, the heater 318may be a wire, which may for example be in the form of a coil, a plate(which may be a multi-layer plate of two or more different materials,one or more of which may be electrically conductive and one or more ofwhich may be electrically non-conductive), a mesh (which may be woven ornon-woven for example, and which again may be similarly multi-layer), afilm heater, etc. The nicotine source 314 in this case is generallytubular or otherwise has an internal aperture for receiving the heater318. The heater 318 may in effect be an integral part of the assembly301 and be provided as part of the housing 302. In this case, as thenicotine source 314 is loaded into the assembly 301 (for example, as thesolid chamber 313 containing the nicotine source 314 is loaded into theassembly 301), the nicotine source 314 surrounds the second heater 318.As an alternative, the heater 318 may be provided integrally with thesolid chamber 313 which holds or contains the nicotine source 314. Inthis alternative, in the case that the solid chamber 313 is disposable,the heater 318 will be replaced when a new solid chamber 313 with afresh nicotine source is loaded into the assembly 301 by the user.

In another example, plural internal heaters 318 may be provided, so asto provide for more efficient heating of the nicotine source 314. Inanother example, the nicotine source 314 may be heated by both one ormore external heaters (like the second heater 215 of the example of FIG.2 ) and by one or more internal heaters (like the second heater 318 ofthe example of FIG. 3 ).

Referring now to FIG. 4 , there is shown a schematic longitudinalcross-sectional view of an example of a cartridge 600 having a liquidchamber 601 for containing aerosolizable liquid 602, and a receptacle orchamber (sometimes referred to herein as “solid chamber”) 603 for anicotine source 604. The liquid 602 corresponds to the liquid describedhereinabove and may have a pH of from 4 to 5, and/or may comprise anacid with a pKa greater than 3, for example. The nicotine source 604corresponds to the nicotine source described hereinabove, isbase-treated, and may have a pH of from 8 to 9.5, for example. In thisexample, the liquid chamber 601 and the nicotine source chamber 603 areprovided as one integral component, either by being formed integrallyinitially or being formed initially of two parts, which are thenassembled in a substantially permanent fashion. The cartridge 600 isarranged so that as the liquid 602 is volatilized so as to produce anaerosol of liquid droplets or sufficiently heated to produce a vapor, atleast some and preferably all or substantially all of the aerosol and/orvapor passes through the nicotine source 604 to pick up flavor from thenicotine source 604. In particular, the free “deprotonated” nicotine inthe nicotine source 604 may undergo acid-base salt formation with theacidic vapor and/or aerosol from the liquid 602. In this way, nicotinemay be drawn out or extracted by the acidic vapor and/or aerosol fromthe nicotine source 604 to increase the amount of nicotine delivery inthe inhalable medium. Furthermore, by passing the acidic vapor/aerosolthrough and over the nicotine source 604, nicotine may be provided inits better tasting, salt form.

In the example of FIG. 4 , the liquid chamber 601 is provided generallycentrally of the cartridge 600. The liquid chamber 601 in the exampleshown is frustoconical in shape, but may have a different shape, such asconical, cylindrical, etc. The liquid chamber 601 is surrounded by anouter shell 605 which defines an annular channel 606 around the outsideof the length of the liquid chamber 601 and which extends from one endof the liquid chamber 601 to the other. The outer shell 605 extendsbeyond a first end wall 607 of the liquid chamber 601 to define achamber 608 beyond the first end wall 607 of the liquid chamber 601. Inthe example shown, both the chamber 608 and the annular channel 606contain the nicotine source 604 and so can be regarded as togetherproviding the solid chamber 603 for the nicotine source 604. In otherexamples, the nicotine source 604 may be provided only in the chamber608, which therefore defines the solid chamber 603 for the nicotinesource 604, and the annular channel 606 is empty. The chamber 608 isclosed off by an end wall 609 which is spaced from the end wall 607 ofthe liquid chamber 601. The end wall 609 may be part of the outer shell605 or may be a separate plastics, rubber cap, or the like. In yet otherexamples, the annular channel 606 contains the nicotine source 604 andthere is no material in the chamber 608, and indeed the chamber 608 maybe omitted and the channel 606 effectively terminates at the end wall609. The channel 606 and/or chamber 608 may be entirely filled withnicotine source 604 or may only contain a portion or plug of nicotinesource 604. The end wall 609 is porous and/or has one or more throughholes 610 to enable the aerosol and/or vapor to exit the cartridge 600to be inhaled by a user. The liquid chamber 601 and the solid chamber603 may each be formed of rigid, watertight and airtight materials, suchas metal, suitable plastics, etc.

The example cartridge 600 shown in FIG. 4 is provided with a heater 611and a wick 612 in (thermal) contact with the heater 611. In thisexample, the heater 611 and the wick 612 are provided as a single unit,often referred to as an “atomizer”. In this case, where the cartridge600 includes an atomizer, such a cartridge is often referred to as a“cartomizer”. The orientation of the heater 611 is shown schematicallyand for example, the heater 611 may be a coil having its longitudinalaxis perpendicular to the longitudinal axis of the cartridge 600 ratherthan parallel as shown in FIG. 4 .

The wick 612 is in contact with the liquid 602. This may be achieved byfor example the wick 612 being inserted through a through hole (notshown) in the second end wall 613 of the liquid chamber 601.Alternatively or additionally, the second end wall 613 may be a porousmember (shown schematically in FIG. 4 by dashed lines) which allowsliquid to pass through from the liquid chamber 601, and the wick 612 maybe in contact with the porous second end wall 613. The second end wall613 may be for example in the form of a porous ceramic disk. A poroussecond end wall 613 of this type helps to regulate the flow of liquidonto the wick 612. The wick 612 is generally absorbent and acts to drawin liquid 602 from the liquid chamber 601 by capillary action. The wick612 is preferably non-woven and may be for example a cotton or woolmaterial or the like, or a synthetic material, including for examplepolyester, nylon, viscose, polypropylene or the like.

In use, the cartridge 600 is connected by the user to a battery sectionof an assembly (not shown) to enable the heater 611 to be powered. Whenthe heater 611 of the atomizer is powered (which may be instigated forexample by the user operating a button of the overall assembly or by apuff detector of the overall assembly, as is known per se), liquid 602drawn in from the liquid chamber 601 by the wick 612 is heated by theheater 611 to volatilize or vaporize the liquid. As the user draws on amouthpiece of the overall assembly, the vapor and/or aerosol passes intothe annular channel 606 around the outside of the length of the liquidchamber 601 and into the chamber 608 as shown by the arrows A. The vaporand/or aerosol picks up flavor from the nicotine source 604 and entrainsone or more components thereof. When the vapor/aerosol contacts thenicotine source 604, the free “deprotonated” nicotine in the nicotinesource 604 may undergo acid-base salt formation with the acidic vaporand/or aerosol from the liquid 602. In this way, nicotine may be drawnout or extracted by the acidic vapor and/or aerosol from the nicotinesource 604 to increase the amount of nicotine delivery in the inhalablemedium. Furthermore, by passing the acidic vapor/aerosol through andover the nicotine source 604, nicotine may be provided in its bettertasting, salt form. The vapor and/or aerosol can then exit the cartridge600 through the end wall 609 as shown by the arrow B. Optionally, a oneway valve 614 may be provided inside the end wall 609 so that the vaporand/or aerosol can only exit the cartridge 600 and cannot back-flow tothe heater 611 or the electronics of the assembly as a whole.

Referring now to FIG. 5 , there is shown a schematic longitudinalcross-sectional view of another example of a cartridge 700 having achamber (sometimes referred to herein as “liquid chamber”) 701 forcontaining aerosolizable liquid (sometimes referred to herein as simply“liquid”) 702 and a chamber (sometimes referred to herein as “solidchamber”) 703 which defines a chamber 708 for containing a nicotinesource 704. The liquid 702 corresponds to the liquid describedhereinabove and may have a pH of from 4 to 5, and/or may comprise anacid with a pKa greater than 3, for example. The nicotine source 704corresponds to the nicotine source described hereinabove, isbase-treated, and may have a pH of from 8 to 9.5, for example. In thefollowing description and in FIG. 5 , components and features that arethe same as or similar to the corresponding components and features ofthe example described with reference to FIG. 4 have the same referencenumeral but increased by 100. For the sake of brevity, the descriptionof those components and features will not be repeated in its entiretyhere.

In this example, the liquid chamber 701 and the solid chamber 703 of thecartridge 700 are provided as separate components, which are detachablyconnected to each other in use. The liquid chamber 701 and the solidchamber 703 may for example be clipped or otherwise detachably fixed toeach other, or for example, the solid chamber 703 may simply rest on orbe a tight friction fit on the liquid chamber 701. The cartridge 700 isarranged so that as the liquid 702 is volatilized so as to produce anaerosol of liquid droplets or sufficiently heated to produce a vapor, atleast some and preferably all or substantially all of the aerosol and/orvapor passes through the nicotine source 704 to pick up flavor from thenicotine source 704 and entrains one or more components thereof. Whenthe vapor/aerosol contacts the nicotine source 704, the free“deprotonated” nicotine in the nicotine source 704 may undergo acid-basesalt formation with the acidic vapor and/or aerosol from the liquid 702.In this way, nicotine may be drawn out or extracted by the acidic vaporand/or aerosol from the nicotine source 704 to increase the amount ofnicotine delivery in the inhalable medium. Furthermore, by passing theacidic vapor/aerosol through and over the nicotine source 704, nicotinemay be provided in its better tasting, salt form.

In this example, the liquid chamber 701 is surrounded by an outer shell705 which defines an annular channel 706 around the outside of thelength of the liquid chamber 701 and which extends from one end of theliquid chamber 701 to the other. The outer shell 705 extends beyond afirst end wall 707 of the liquid chamber 701 and terminates in an endwall 709. The end wall 709 may be a separate plastics, rubber cap, orthe like. The end wall 709 is porous and/or has one or more throughholes 710 to enable the aerosol and/or vapor to exit the annular channel706. A one way valve 714 may be provided inside the end wall 709 so thatthe vapor and/or aerosol can only exit the annular channel 706 at theend remote from the heater 711 and wick 712 and cannot back-flow to theheater 711 or the electronics of the assembly as a whole. The nicotinesource chamber 703 is located in use over the end wall 709 so that vaporand/or aerosol exiting through the end wall 709 passed into the solidchamber 703. The solid chamber 703 has an exit aperture and/or or aporous end wall 715 to enable the aerosol and/or vapor to exit thecartridge 700 to be inhaled by a user.

In use, the cartridge 700 is connected by the user to a battery sectionof an assembly (not shown) to enable the heater 711 to be powered. Whenthe heater 711 of the atomizer is powered (which may be instigated forexample by the user operating a button of the overall assembly or by apuff detector of the overall assembly as is known per se), liquid 702drawn in from the liquid chamber 701 through the end wall 713 by thewick 712 is heated by the heater 711 to volatilize or vaporize theliquid. As the user draws on a mouthpiece of the overall assembly, thevapor and/or aerosol passes into the annular channel 706 around theoutside of the length of the liquid chamber 701 towards the end wall 709of the outer shell 705 as shown by the arrows A. The vapor and/oraerosol then passes through the end wall 709 (via the one-way valve 714if present) and into the solid chamber 703 where it picks up flavor fromthe nicotine source 704 contained in the solid chamber 703, and entrainsone or more components of the nicotine source 704. When thevapor/aerosol contacts the nicotine source 704, the free “deprotonated”nicotine in the nicotine source 704 may undergo acid-base salt formationwith the acidic vapor and/or aerosol from the liquid 702. In this way,nicotine may be drawn out or extracted by the acidic vapor and/oraerosol from the nicotine source 704 to increase the amount of nicotinedelivery in the inhalable medium. Furthermore, by passing the acidicvapor/aerosol through and over the nicotine source 704, nicotine may beprovided in its better tasting, salt form. The vapor and/or aerosol canthen exit the cartridge 700 through the end wall 715 of the solidchamber 703 as shown by the arrow B.

The examples shown in FIGS. 4 and 5 are particularly suitable for usewith so-called modular or “e go” products, in which the cartomizer isfitted to a battery section (not shown), typically by a screw thread, abayonet fitting or the like. The cartomizer as a whole is typicallydiscarded after use and a new, replacement cartomizer used. As analternative, it may be possible for the user to re-use the cartridge byrefilling the liquid and/or replacing the solid material from time totime as necessary.

The examples shown in FIGS. 4 and 5 may easily be adapted for use withother types of an electronic tobacco hybrid device, which are known perse. There are for example so-called “look alike e cigarette” or“cig-alike” assemblies which are generally small and have a form andappearance similar to a conventional cigarette. In such assemblies, theliquid chamber typically includes some wadding material, of for examplecotton or the like, for holding the liquid. The cartridge or cartomizerin such known assemblies is typically disposable as a whole, but it maybe possible to refill the liquid and/or replace the sold material inexamples that use an embodiment of the present invention. As anotherexample, there are so-called tank assemblies or personal vaporizers,which generally have large liquid chambers for holding relatively largevolumes of liquid and also provide for advanced functions that allowusers to control a number of aspects of the assembly.

As an alternative to any of the cartomizer arrangements discussed above,the atomizer (i.e. the heater and the wick) for the liquid may beprovided separately of the liquid and solid chambers. The atomizer mayfor example be provided as part of the battery section of the overallassembly to which the cartridge is detachably fitted by the user in use.

In any of the examples described above in relation to FIGS. 4 and 5 ,there may also be provided a heater for the nicotine source so as to“pre-heat” it. This heater may be provided as part of the cartridge oras part of the battery section of the assembly to which the cartridge isfitted in use.

EXAMPLES

Several experiments were tested to evaluate the effects of using anacidic vapor and/or aerosol on nicotine extraction from a nicotinesource to provide an enhanced amount of nicotine delivery in aninhalable medium.

In this example, the objective was to test whether using an acidicaerosolizable liquid would extract nicotine from pH-treated tobacco toincrease the amount of nicotine delivery in the inhalable medium. Threeaerosolizable liquids were prepared for the experiments:

-   -   1-C, a control sample an e-liquid composition of glycerol (17%        w/w), propylene glycol (71% w/w) and water (12% w/w);    -   1-BA, a sample containing 0.04% by weight benzoic acid and the        e-liquid; and    -   1-LA, a sample containing 0.04% by weight lactic acid and the        e-liquid.

The solid, nicotine-containing material used was a tobacco blend,treated with base to have a pH of 8.5. The materials were loaded onto astandard test system as pods and the liquid was heated; the heaterelement had a power of 7.5 W. The vapor/aerosol formed from the liquidwas then passed through or over the pH-treated tobacco composition,entraining one or more components thereof to provide an inhalablemedium, which passes to a detector through an outlet.

During one experiment, the system performed 60 puffs in total per pod,formed of three 20-puff blocks, measuring the nicotine delivery at each20-puff interval. The puffing was done using a 55/3/30 regime (55 mlpuff of 3-second duration every 30 seconds). The measurements wererepeated four times for each sample. A summary of the results is shownin the tables below.

Puff block=20

Nicotine StDev SampleMean (ug/Puff) (ug/Puff) 1-C 67.19 11.97 1-BA 78.585.80 1-LA 99.50 8.13

Puff block=40

Nicotine StDev SampleMean (μg/Puff) (μg/Puff) 1-C 50.91 8.13 1-BA 49.378.01 1-LA 60.38 8.83

Puff block=60

Nicotine StDev SampleMean (μg/Puff) (μg/Puff) 1-C 24.92 3.20 1-BA 30.404.25 1-LA 28.50 8.88

Referring to FIG. 6 , a graph of the results from the experimentsdescribed above are shown, and demonstrates examples of nicotinedelivery from assemblies according to embodiments of the invention, aswell as a comparative assembly.

For the 1-20 puff block measurement on each sample, the nicotinedelivery has increased for the acidified liquids. For benzoic acidcontaining liquids, the nicotine delivery has increased from 67.2μg/puff (control, 1-C) to 79 μg/puff (1-BA). For lactic acid containingliquids, the nicotine delivery has increased from 67.2 μg/puff (control,1-C) to 100 μg/puff (1-LA).

Accordingly, the results of the experiments show that the use of anacidic vapor/aerosol (such as one formed from a liquid containingbenzoic acid or lactic acid in 1-BA or 1-LA, respectively) increases theamount of nicotine delivered to the user, compared to a neutralvapor/aerosol (such as the liquid used in 1-C).

Furthermore, the above results show that the total nicotine contentremoved from the solid tobacco is higher when an acidic vapor/aerosol isused. That is, a higher amount of nicotine is extracted from the tobaccowhen using an acidic vapor/aerosol (1-BA, 1-LA) compared to a neutralvapor/aerosol (1-C). Thus, in some embodiments the assembly allows forthe rate of nicotine extraction to be increased, as well as the totalamount of nicotine that is available to be extracted from the nicotinesource to be increased.

As used herein, “aerosol generating agent” refers to a compound ormixture that promotes the generation of an aerosol. Anaerosol-generating agent may promote the generation of an aerosol bypromoting an initial vaporization and/or the condensation of a gas to aninhalable solid and/or liquid aerosol.

In general, any suitable aerosol-generating agent or agents may beincluded in the aerosolizable liquid or nicotine source. Suitableaerosol generating agents include, but are not limited to: a polyol suchas sorbitol, glycerol, and glycols like propylene glycol or triethyleneglycol; a non-polyol such as monohydric alcohols, high boiling pointhydrocarbons, acids such as lactic acid, glycerol derivatives, esterssuch as diacetin, triacetin, triethylene glycol diacetate, triethylcitrate or myristates including ethyl myristate and isopropyl myristateand aliphatic carboxylic acid esters such as methyl stearate, dimethyldodecanedioate and dimethyl tetradecanedioate.

As used herein, the terms “flavor” and “flavoring” refer to materialswhich, where local regulations permit, may be used to create a desiredtaste or aroma in a product for adult consumers. They may includeextracts (e.g., liquorice, hydrangea, Japanese white bark magnolia leaf,chamomile, fenugreek, clove, menthol, Japanese mint, aniseed, cinnamon,herb, wintergreen, cherry, berry, peach, apple, Drambuie, bourbon,scotch, whiskey, spearmint, peppermint, lavender, cardamom, celery,cascarilla, nutmeg, sandalwood, bergamot, geranium, honey essence, roseoil, vanilla, lemon oil, orange oil, cassia, caraway, cognac, jasmine,ylang-ylang, sage, fennel, piment, ginger, anise, coriander, coffee, ora mint oil from any species of the genus Mentha), flavor enhancers,bitterness receptor site blockers, sensorial receptor site activators orstimulators, sugars and/or sugar substitutes (e.g., sucralose,acesulfame potassium, aspartame, saccharine, cyclamates, lactose,sucrose, glucose, fructose, sorbitol, or mannitol), and other additivessuch as charcoal, chlorophyll, minerals, botanicals, or breathfreshening agents. They may be imitation, synthetic or naturalingredients or blends thereof. They may be in any suitable form, forexample, oil, liquid, or powder.

For the avoidance of doubt, where in this specification the term“comprises” is used in defining the invention or features of theinvention, embodiments are also disclosed in which the invention orfeature can be defined using the terms “consists essentially of” or“consists of” in place of “comprises”.

As used herein, the term pH is used as a reference to the pH measured atroom temperature, i.e. at 20-22° C. In some embodiments, roomtemperature is 20° C.

The above embodiments are to be understood as illustrative examples ofthe invention. Further embodiments of the invention are envisaged. It isto be understood that any feature described in relation to any oneembodiment may be used alone, or in combination with other featuresdescribed, and may also be used in combination with one or more featuresof any other of the embodiments, or any combination of any other of theembodiments. Furthermore, equivalents and modifications not describedabove may also be employed without departing from the scope of theinvention, which is defined in the accompanying claims.

The various embodiments described herein are presented only to assist inunderstanding and teaching the claimed features. These embodiments areprovided as a representative sample of embodiments only, and are notexhaustive and/or exclusive. It is to be understood that advantages,embodiments, examples, functions, features, structures, and/or otheraspects described herein are not to be considered limitations on thescope of the invention as defined by the claims or limitations onequivalents to the claims, and that other embodiments may be utilizedand modifications may be made without departing from the scope of theclaimed invention. Various embodiments of the invention may suitablycomprise, consist of, or consist essentially of, appropriatecombinations of the disclosed elements, components, features, parts,steps, means, etc., other than those specifically described herein. Inaddition, this disclosure may include other inventions not presentlyclaimed, but which may be claimed in future.

1. An aerosol generating assembly comprising: a solid,nicotine-containing material having a pH of at least 7; an aerosolizableliquid comprising an acid, and having a pH of at least 2 and less than7; and wherein the assembly is configured to heat the aerosolizableliquid to form a vapor and/or an aerosol, wherein the vapor/aerosol iscontacted with the solid, nicotine-containing material to entrain one ormore components thereof, and thus forming an inhalable medium.
 2. Anaerosol generating assembly according to claim 1, wherein the solid,nicotine-containing material comprises a tobacco material.
 3. An aerosolgenerating assembly according to claim 1, wherein the pH of the solid,nicotine-containing material is of from 8 to 9.5 or from 8.5 to
 9. 4. Anaerosol generating assembly according to claim 1, wherein theaerosolizable liquid has a pH of from 4 to 5 or from 4.3 to 4.8.
 5. Anaerosol generating assembly according to claim 1, wherein the differencebetween the pH of the solid nicotine-containing material and the pH ofthe aerosolizable liquid is of from 3.0 and 5.5.
 6. An aerosolgenerating assembly according to claim 1, wherein the acid has a vaporpressure at 25° C. of from 0.1 Pa to 2.5 kPa.
 7. An aerosol generatingassembly according to claim 1, wherein the aerosolizable liquid has anamount of acid of from 0.001 to 5% by weight.
 8. An aerosol generatingassembly according to claim 1, wherein the assembly is configured suchthat the solid, nicotine-containing material is heated only by thevapor/aerosol.
 9. An aerosol generating assembly comprising: a solid,nicotine-containing material having a pH of at least 7; an aerosolizableliquid comprising an acid, the acid with a pKa greater than 0.5; andwherein the assembly is configured to heat the aerosolizable liquid toform a vapor and/or an aerosol, wherein the vapor/aerosol is contactedwith the solid, nicotine-containing material to entrain one or morecomponents thereof, and thus forming an inhalable medium.
 10. An aerosolgenerating assembly according to claim 9, wherein the pKa of the acid isgreater than 3, or is from 3.7 to 4.3.
 11. An aerosol generatingassembly according to claim 9, wherein the pH of the solid,nicotine-containing material is of from 8 to 9.5 or from 8.5 to
 9. 12. Acartridge for use in an assembly for generating an inhalable medium, thecartridge comprising an aerosolizable liquid comprising an acid in afirst chamber, the aerosolizable liquid having a pH of at least 2 andless than 7, and a solid, nicotine-containing material in a secondchamber, the solid, nicotine-containing material having a pH of at least7.
 13. A cartridge according to claim 12, wherein the aerosolizableliquid has a pH of from 4 to 5 or from 4.3 to 4.8.
 14. A cartridgeaccording to claim 12, wherein the solid, nicotine-containing materialhas a pH of from 8 to 9.5 or from 8.5 to
 9. 15. A cartridge according toclaim 12, wherein the acid has a vapor pressure at 25° C. of from 0.1 Pato 2.5 kPa.
 16. A method of generating an inhalable medium using anassembly comprising an aerosolizable liquid comprising an acid, theaerosolizable liquid having a pH of at least 2 and less than 7, and asolid, nicotine-containing material having a pH of at least 7, themethod comprising: heating the aerosolizable liquid to form a vaporand/or an aerosol; forming an inhalable medium, by contacting theaerosolizable liquid in the form of a vapor and/or an aerosol with thesolid, nicotine-containing material to entrain one or more componentsthereof.
 17. A method according to claim 16, wherein the aerosolizableliquid has a pH of from 4 to 5 or from 4.3 to 4.8.
 18. A methodaccording to claim 16, wherein the vapor pressure of the acid at 25° C.is of from 0.1 Pa to 2.5 kPa.
 19. Use of an acidic vapor and/or aerosolto extract nicotine from a solid, nicotine-containing material having apH of more than 7, wherein the rate of nicotine extraction exceeds therate of nicotine-salt formation in the solid, thereby providing anincreased nicotine content in the vapor and/or aerosol as compared tousing a neutral vapor and/or aerosol.
 20. A kit comprising: (i) a liquidpod containing an aerosolizable liquid comprising an acid, theaerosolizable liquid having a pH of from at least 2 and less than 7; and(ii) a nicotine-containing pod, containing a solid, nicotine-containingmaterial having a pH of at least 7; wherein the liquid andnicotine-containing pod are configured for use in an assembly for use ingenerating an inhalable medium, the assembly being such that in use, aninhalable medium is generated by contacting the aerosolizable liquid inthe form of a vapor and/or an aerosol with the solid,nicotine-containing material to entrain one or more components thereof.